Grade 1Reading: grades 1-2AdditionSubtractionSkip countingPlace valueMissing addends
The Golden Dino Egg Mystery
A rare golden egg has vanished from the Dino Island Camp! The Rescue Club needs to search for clues, track down the dino thief, and return the egg safely. Let us start the hunt!
Suspects
Possible suspects
Cross off a row as each clue rules it out. On screen, tap a row.
21 of 21 still in play
| Name | Dino Partner | Explorer Tool | Glove Color | Cap Color | Camp Snack |
|---|---|---|---|---|---|
| Maya | Pterodactyl | Glow Torch | Red Gloves | Green Cap | Juicy Berries |
| Ella | Pterodactyl | Glow Torch | Red Gloves | Green Cap | Crunchy Ferns |
| Leo | T-Rex | Sling Bag | Red Gloves | Brown Fedora | Crunchy Ferns |
| Abby | T-Rex | Brass Compass | Blue Gloves | Yellow Cap | Juicy Berries |
| Zoe | Triceratops | Super Map | Blue Gloves | Yellow Cap | Sweet Melon |
| Sara | Pterodactyl | Super Map | Red Gloves | Green Cap | Juicy Berries |
| Max | Stegosaurus | Glow Torch | Red Gloves | Green Cap | Crunchy Ferns |
| Finn | T-Rex | Mega Lens | Red Gloves | Green Cap | Crunchy Ferns |
| Cole | T-Rex | Mega Lens | Blue Gloves | Brown Fedora | Sweet Melon |
| Luke | Triceratops | Glow Torch | Red Gloves | Brown Fedora | Sweet Melon |
| Ruby | Pterodactyl | Sling Bag | Blue Gloves | Yellow Cap | Sweet Melon |
| Cody | T-Rex | Super Map | Blue Gloves | Green Cap | Sweet Melon |
| Mia | T-Rex | Sling Bag | Red Gloves | Green Cap | Juicy Berries |
| Toby | Stegosaurus | Brass Compass | Red Gloves | Green Cap | Crunchy Ferns |
| Luna | Pterodactyl | Brass Compass | Blue Gloves | Brown Fedora | Sweet Melon |
| Lily | Raptor | Mega Lens | Red Gloves | Green Cap | Crunchy Ferns |
| Jack | Raptor | Mega Lens | Blue Gloves | Green Cap | Crunchy Ferns |
| Zack | Stegosaurus | Super Map | Blue Gloves | Green Cap | Sweet Melon |
| Owen | T-Rex | Mega Lens | Blue Gloves | Yellow Cap | Sweet Melon |
| Kate | T-Rex | Mega Lens | Red Gloves | Brown Fedora | Sweet Melon |
| Sam | Pterodactyl | Sling Bag | Blue Gloves | Yellow Cap | Juicy Berries |
Clue 1
Addition
We must count the dino bones we found today. Let us add the small bones and big bones together.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
T
11
5
3
T
11
5
15
3
6
12
7
3
20
9
7
T
11
13
20
3
T
11
5
3
8
2
14
20
20
4
7
17
18
14
20
20
6 + 5 =T
3 + 6 =N
2 + 2 =C
4 + 1 =H
10 + 4 =A
4 + 8 =D
6 + 11 =M
9 + 4 =U
4 + 2 =F
6 + 9 =I
8 + 12 =S
5 + 2 =O
1 + 1 =R
6 + 2 =B
2 + 1 =E
6 + 12 =P
0/16 letters found
Clue 2
Subtraction
The sneaky thief took some of our water bottles. Subtract the lost bottles to see how many we have left.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
T
15
1
19
3
11
19
13
4
17
19
18
T
15
5
19
6
9
17
12
16
19
3
8
11
T
15
1
19
2
10
6
16 - 1 =T
11 - 9 =M
20 - 7 =A
14 - 8 =D
4 - 3 =H
14 - 3 =N
18 - 2 =V
4 - 1 =S
7 - 2 =R
20 - 1 =E
20 - 2 =F
15 - 3 =O
6 - 2 =K
15 - 5 =U
17 - 8 =G
15 - 7 =I
18 - 1 =L
0/17 letters found
Clue 3
Skip counting
We find tracks in the soft sand. We count the toes by twos to follow the path.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
W
90
42
6
39
55
50
24
27
14
55
50
27
15
30
6
42
14
50
140
80
30
20
15
42
6
39
39
20
26
14
28
50
20
140
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110W
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45O
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160S
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33C
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, ___, 45, 48E
Skip-count by 10s. Fill the blank: 10, 20, ___, 40, 50Y
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65U
Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, ___, 90, 100B
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32I
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, ___, 16, 18R
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30P
Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30D
Skip-count by 5s. Fill the blank: 5, 10, ___, 20, 25H
Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, ___, 22, 24T
Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, ___, 55, 60N
Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10F
0/16 letters found
Clue 4
Place value
The tracker box has tens and ones on the screen. Let us look at the digits to unlock the next map.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
A
54
79
46
51
23
75
92
23
46
77
77
15
14
A
54
58
81
77
59
59
51
15
92
75
77
79
13
76
75
77
76
What number has 5 tens and 4 ones?A
What number has 7 tens and 5 ones?H
What number has 1 ten and 5 ones?N
What number has 2 tens and 3 ones?G
What number has 5 tens and 8 ones?P
What number has 7 tens and 6 ones?S
What number has 5 tens and 1 one?I
What number has 9 tens and 2 ones?T
What number has 5 tens and 9 ones?L
What number has 8 tens and 1 one?F
What number has 1 ten and 4 ones?C
What number has 4 tens and 6 ones?R
What number has 7 tens and 9 ones?B
What number has 7 tens and 7 ones?E
What number has 1 ten and 3 ones?U
0/15 letters found
Clue 5
Missing addends — the last clue
We need ten logs to cross the mud. We have seven logs. How many more do we need to find?
First solve each problem. Then find each answer in the list below and cross that sentence out. One sentence will be left — that's exactly what the villain did!
Step 1 — solve these
4 + ___ = 12
4 + ___ = 14
5 + ___ = 8
4 + ___ = 8
5 + ___ = 12
3 + ___ = 14
10 + ___ = 22
7 + ___ = 16
4 + ___ = 6
7 + ___ = 12
4 + ___ = 10
Step 2 — cross out the sentence with each answer
1.The villain sneaks past the sleeping guard, then splashes into the river.
2.The villain climbs the tall rock wall, then hides in a secret cave.
3.The villain runs through the jungle, then zips down a long vine.
4.The villain climbs the tall rock wall, then jumps into the treehouse.
5.The villain crosses the rope bridge, then zips down a long vine.
6.The villain runs through the jungle, then jumps into the treehouse.
7.The villain rides a fast dinosaur, then jumps into the treehouse.
8.The villain crosses the rope bridge, then splashes into the river.
9.The villain sneaks past the sleeping guard, then disappears in the thick fog.
10.The villain rides a fast dinosaur, then zips down a long vine.
11.The villain crosses the rope bridge, then hides in a secret cave.
12.The villain runs through the jungle, then hides in a secret cave.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Golden Dino Egg Mystery
Culprit: Ella (Pterodactyl · Glow Torch · Red Gloves · Green Cap · Crunchy Ferns)
- Clue 1 (Addition): "THE THIEF DOES NOT USE THE BRASS COMPASS"6 + 5 = 11 (T) · 3 + 6 = 9 (N) · 2 + 2 = 4 (C) · 4 + 1 = 5 (H) · 10 + 4 = 14 (A) · 4 + 8 = 12 (D) · 6 + 11 = 17 (M) · 9 + 4 = 13 (U) · 4 + 2 = 6 (F) · 6 + 9 = 15 (I) · 8 + 12 = 20 (S) · 5 + 2 = 7 (O) · 1 + 1 = 2 (R) · 6 + 2 = 8 (B) · 2 + 1 = 3 (E) · 6 + 12 = 18 (P)
- Clue 2 (Subtraction): "THE SNEAK LEFT RED GLOVES IN THE MUD"16 - 1 = 15 (T) · 11 - 9 = 2 (M) · 20 - 7 = 13 (A) · 14 - 8 = 6 (D) · 4 - 3 = 1 (H) · 14 - 3 = 11 (N) · 18 - 2 = 16 (V) · 4 - 1 = 3 (S) · 7 - 2 = 5 (R) · 20 - 1 = 19 (E) · 20 - 2 = 18 (F) · 15 - 3 = 12 (O) · 6 - 2 = 4 (K) · 15 - 5 = 10 (U) · 17 - 8 = 9 (G) · 15 - 7 = 8 (I) · 18 - 1 = 17 (L)
- Clue 3 (Skip counting): "WE FOUND CRUNCHY FERNS BY THE FOOTPRINTS"Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, ___, 100, 110 = 90 (W) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, ___, 42, 45 = 39 (O) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, ___, 150, 160 = 140 (S) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, ___, 30, 33 = 27 (C) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, ___, 45, 48 = 42 (E) · Skip-count by 10s. Fill the blank: 10, 20, ___, 40, 50 = 30 (Y) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, ___, 60, 65 = 55 (U) · Skip-count by 10s. Fill the blank: 10, 20, 30, 40, 50, 60, 70, ___, 90, 100 = 80 (B) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, ___, 30, 32 = 28 (I) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, ___, 16, 18 = 14 (R) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, ___, 28, 30 = 26 (P) · Skip-count by 3s. Fill the blank: 3, 6, 9, 12, 15, 18, 21, ___, 27, 30 = 24 (D) · Skip-count by 5s. Fill the blank: 5, 10, ___, 20, 25 = 15 (H) · Skip-count by 2s. Fill the blank: 2, 4, 6, 8, 10, 12, 14, 16, 18, ___, 22, 24 = 20 (T) · Skip-count by 5s. Fill the blank: 5, 10, 15, 20, 25, 30, 35, 40, 45, ___, 55, 60 = 50 (N) · Skip-count by 2s. Fill the blank: 2, 4, ___, 8, 10 = 6 (F)
- Clue 4 (Place value): "A BRIGHT GREEN CAP FELL IN THE BUSHES"What number has 5 tens and 4 ones? = 54 (A) · What number has 7 tens and 5 ones? = 75 (H) · What number has 1 ten and 5 ones? = 15 (N) · What number has 2 tens and 3 ones? = 23 (G) · What number has 5 tens and 8 ones? = 58 (P) · What number has 7 tens and 6 ones? = 76 (S) · What number has 5 tens and 1 one? = 51 (I) · What number has 9 tens and 2 ones? = 92 (T) · What number has 5 tens and 9 ones? = 59 (L) · What number has 8 tens and 1 one? = 81 (F) · What number has 1 ten and 4 ones? = 14 (C) · What number has 4 tens and 6 ones? = 46 (R) · What number has 7 tens and 9 ones? = 79 (B) · What number has 7 tens and 7 ones? = 77 (E) · What number has 1 ten and 3 ones? = 13 (U)
- Clue 5 (Missing addends): surviving statement (box 1) → Ella4 + ___ = 12 = 8 · 4 + ___ = 14 = 10 · 5 + ___ = 8 = 3 · 4 + ___ = 8 = 4 · 5 + ___ = 12 = 7 · 3 + ___ = 14 = 11 · 10 + ___ = 22 = 12 · 7 + ___ = 16 = 9 · 4 + ___ = 6 = 2 · 7 + ___ = 12 = 5 · 4 + ___ = 10 = 6
About this mystery
- Grade level
- Grade 1 math
- Math topics
- Addition, Subtraction, Skip counting, Place value, Missing addends
- Reading level
- grades 1-2
- Theme
- The Golden Dino Egg Mystery — set in Dino Island Camp
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects